In the related art, object recognition technology is used to identify a target object according to similarity between feature values of the target object extracted from image data acquired by an image sensor and collation data (feature values) of various known items. Such an object recognition technology can be applied to a checkout system of a store to identify items to be purchased such as fruits and vegetables that may not have code symbols, and register sales of the identified items.
In a file used for the object recognition, collation data (feature value) of various known items are registered in advance. However, when the collation data (feature values) registered in the file is improper, similarity between the target item and the corresponding registered item may be low, and the identification of the target item may be not carried out properly.